Pipe fitting covers for angled joints such as elbow joints, tee joints, etc. are known in the art. For example, Dunn, U.S. Pat. No. 3,153,546 discloses a split jacket housing for pipe elbows having sections with overlapping connecting flanges and interengageable ribs and grooves. Carlson, U.S. Pat. No. 3,307,590 discloses semi-circular foamed urethane sections surrounded by aluminum shell segments.
Pipe fitting covers of the type mentioned above being formed from a pair of semi-circular sections are disadvantageous because they have seams which may split or crack and thereby eventually leak. Unless the pipe insulation, especially at an angled pipe joint is tightly sealed, the pipe insulation customarily used around the pipe can fail due to moisture intrusion, causing undesired energy loss. The pipe system itself may also fail due to corrosion arising from the infiltration of moisture under the jacketing surrounding the insulation.
More recently, with the development of thermoplastics and other flexible resilient materials, pipe covers have been constructed as one piece units to eliminate the seams of sectioned covers. The single piece units are formed as a single integral structure having opposed ends which are folded about each other around the inner radius of the angled joint when the cover is wrapped therearound. As used herein, the term "angled joint" means any juncture of at least two pipes which come together at an angle with respect to each other. The most common examples are elbow joints and tee joints (pipes that meet at a 90.degree. angle).
Such single piece covers have been made by Proto Corporation, Zeston, Inc. and Speedline Manufacturing Company. In order to secure the cover about the angled joint, the opposed ends are folded over each other and secured together and to the underlying pipe insulation. Common means of securing the opposed ends together are adhesives or a pair of threaded tacks which are inserted into the opposed corners of the top end of the cover and then inserted into a corresponding portion of the bottom end.
These methods, however, have had limited success. Adhesives are disadvantageous because the opposed ends tend to separate from each other especially when the adhesive cracks due to the often severe temperature and humidity conditions in vicinity of the pipe joint. There are also major disadvantages with the two tack attachment system. First, the threaded tacks typically used are expensive and each tack may comprise as much as 15% of the total cost of the cover. It would therefore be desirable to eliminate one of the tacks used to secure the cover about the angled joint. Second, the area of the top end of the cover between the two tacks has a tendency to buckle when the tacks are inserted through the top end and bottom end. As a result, the area of the cover between the two tacks does not close as tightly as is necessary to eliminate the elements leading to the failure of the pipe insulation and the pipe itself.
There is a need in the pipe insulation industry to provide a pipe cover which is tightly secured about an angled joint and thereby overcomes the problems of previously employed pipe cover systems.
It is therefore an object of the present invention to provide a single integral structure pipe cover for covering an angled joint such as an elbow joint, tee joint, etc. which provides greater protection against moisture infiltration, is easier to install and significantly less expensive to produce than known pipe covers.
It is a further object of the invention to provide a novel fastening means to secure a single integral structure pipe cover about an angled joint which avoids the use of multiple fastening means to fasten the cover around an angled joint.
It is another object of the invention to provide a single integral structure pipe cover wherein the terminal edge of the top end of the cover has an arcuate shape so that the top end lies flat against the bottom end of the cover to thereby prevent moisture infiltration.
It is a further object of the invention to provide a method of securing a pipe cover about an angled joint with the use of a single centrally located securing means.